I have been testing 720p recording in CM10 roms recently. It looks like it is not impossible to reach good fps in CM after all.
It was inspired by the maker of MESA kernel an0nym0us_ who used stock camera lib in cm10. Big thanks to him!
My test rom was SJB 8.0 and CM10 nightly 2013.10.06.
Basically I did 3 modifications:
1. Copied camera.semc.so to /system/lib/hw/
2. Modified media_profiles.xml
3. Modified pmem sizes in kernel. Used nAa kernel as base. Free ram is 388 MB at the moment. Still testing it...

The result is good hd recording at near 29.7 fps. The smoothest results come in the camera app found in Super Jelly Bean 8.0. Other apps like stock CM cam and LGCamera produce around 25-27 fps but it can be improved with a tweak.

So here is what to do:
1. Flash kernel (mini_naa720p.img or minipro_naa720p.img or lww_naa720p.img or active_naa720p.img)
2. flash zip in cwm (cm10_enable720p.zip)

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